Stainless steel in jewelry and its characteristics
Why choose stainless steel?
Many metal accessories sold on the site of So Cute by DImi are made of stainless steel.
Always the same anxieties and the same questions: does this article contain nickel? Is stainless steel durable over time?
Here is a little topo so that you are on top ;-)
1. What is stainless steel?
Stainless steel, also called stainless steel, is a metal that is widely used in all areas of domestic and industrial life, due to its great stainless qualities.
It is an alloy of iron, chromium, nickel and carbon necessary to guarantee the formation of a self-healing surface layer that makes it stainless.
2. What is the composition of stainless steel?
- More than 50%iron.
- Chromium & carbon. According to the European standard EN 10088-13, a steel is classified as stainless steel if it contains a minimum of 10.5% chromium by mass and a maximum of 1.2% carbon, which will prevent the formation of carbides that are harmful to the material.
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Nickel. It homogenizes the alloy. It provides the properties of flexibility, malleability and resilience (shape memory). The regulations are very strict for jewelry. The European directive on nickel (94/27/CE in its latest version of September 27, 2004) requires that the nickel release rate be 0.5 micrograms per cm 2 (of the part's surface) per week for articles in direct and prolonged contact with the skin. This migration limit is lowered to 0.2 µg/cm²/week for piercing.
That is why most of the alloys containing nickel have been removed. But some are still allowed, such as stainless steels. -
Other elements:
- Manganese is a substitute for nickel. Some series of stainless steel alloys have been developed to cope with uncertainties in nickel supply.
- Molybdenum and copper improve the resistance in most corrosive environments, especially acidic ones (e.g. perspiration), but also in phosphoric and sulfuric solutions.
- Tungsten improves the high temperature resistance of stainless steels.
- Titanium avoids the alteration of the metallurgical structures during hot work, in particular during welding, thus preserving the stainless character of the steel by avoiding chromium depletion.
-Niobium has a much higher melting point than titanium and has similar properties.
- Silicon also plays a role in oxidation resistance.
3. What are the advantages of stainless steel?
Stainless steel has several advantages:
- It is heat malleable and can be engraved.
- It is hypoallergenic. It does not cause any reaction on the skin except in very rare cases.
- It is ecological. Its impact on the environment is low, because it does not release nickel and it can be recycled endlessly ....
- It is almost indestructible and non-deformable.
- It requires little maintenance.
- 100% recyclable
4. Why does stainless steel rust?
Steel can oxidize in certain cases (for example, very high temperatures: over 800°C). Under normal conditions of use, the chromium oxide contained in stainless steel develops a transparent oxide film on the metal. This film is a barrier to any intrusion that could lead to oxidation (even if the metal has suffered an impact, the protective barrier will reform).
Stainless steel with these characteristics will not oxidize or turn black in the face of daily aggressions: water, household products, sea water, cosmetics, perspiration, etc.
5. Can stainless steel go in water?
It depends on the quality of your stainless steel jewelry! It is possible to take a shower or a bath with your stainless steel jewelry without it altering. On the other hand, it is not advisable to bathe for a long time in a swimming pool, because chlorine is very aggressive. It eliminates the invisible film created by the chrome to protect the jewelry.
It is also better to remove your jewelry before swimming in the sea or ocean. The salt water could tarnish the jewelry and cause it to rust.
6. 201 stainless steel, 304 stainless steel or 316 stainless steel
| Advantages | Disadvantages | |
| 201 stainless steel |
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| 304 Stainless Steel |
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| 316 stainless steel |
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